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Recent advances in sensor technology have led to the development of new hyper-spectral instruments capable of measuring reflected radiation over a wide range of wavelengths. These instruments can be used to assess the diverse characteristics of vegetation recovery that are only noticeable in certain parts of the electromagnetic spectrum. In this research, such instruments were used to study vegetation recovery following a forest fire in a Mediterranean ecosystem. The specific event occurred in an area called El Rodenal of Guadalajara (in Central Spain) between 16 and 21 July 2005. Remotely sensed hyper-spectral multitemporal data were used to assess the forest vegetation response following the fire. These data were also combined with remotely sensed fire severity data and satellite high temporal resolution data. Four Airborne Hyperspectral Scanner (AHS) hyper-spectral images, 361 Moderate Resolution Imaging Spectroradiometer (MODIS) images, field data, and ancillary information were used in the analysis. The total burned area was estimated to be 129.4 km2. AHS-derived fire severity level-of-damage assessments were estimated using the normalized burn ratio (NBR). Post-fire vegetation recovery was assessed according to a spectral unmixing analysis of the AHS hyper-spectral images and the normalized difference vegetation index (NDVI), as calculated from the MODIS time series. Combining AHS hyper-spectral images with field data provides reliable estimates of burned areas and fire severity levels-of-damage. This combination can also be used to monitor post-fire vegetation recovery trends. MODIS time series were used to determine the types and rates of vegetation recovery after the fire and to support the AHS-based estimates. Data and maps derived using this method may be useful for locating priority intervention areas and planning forest restoration projects. © 2013 Copyright Taylor and Francis Group, LLC.

Aim of study The following paper presents an inter-comparison of three global products MCD45A1 (MODISMODerate resolution Imaging Spectrometer-Burned Area Product), L3JRC (Terrestrial Ecosystem Monitoring Global Burnt Area Product), and GLOBCARBON Burnt Area Estimate (BAE) Product; and three local products, two of them based on MODIS data and the other one based on MERIS (MEdium Resolution Imaging Spectrometer) data. Area of study The study was applied to the Galician forest fires occurred in 2006. Material and methods Materials used involved the three already mentioned global products together with two MODIS and one MERIS reflectance images, and MODIS thermal anomalies. The algorithm we used, which is based on the determination of thresholds values on infrared bands, allowed the identification of burned pixels. The determination of such threshold values was based on the maximum spatial correlation between MODIS thermal anomalies, and infrared reflectance values. This methodology was applied to MODIS and MERIS reflectance bands, and to the NBR (Normalized Burn Ratio). Burned area validation was evaluated using burned area polygons as derived from an AWiFS (Advanced Wide Field Sensor) image of 60 m pixel size. Main results Best results were reached when using the MERIS infrared bands, followed by the MODIS infrared bands. Worst results were reached when using the MCD45A1 product, which clearly overestimated; and when using the L3JRC product, which clearly underestimated. Research highlights Since the efficiency of the performance of the available burned area products is highly variable, much work is needed in terms of comparison among the available sensors, the burned area mapping algorithms and the resulting products.

Satellite-based strategies for burned area mapping may rely on two types of remotely sensed data postfire reflectance images and active fire detection. This study uses both methods in a synergistic way. In particular, burned area mapping is carried out using MCD43B4 [Moderate Resolution Imaging Spectrometer (MODIS); Terra 1 Aqua nadir bidirectional reflectance distribution function (BRDF); adjusted reflectance 16-day L3 global 1-km sinusoidal grid V005 (SIN)] postfire datasets and MODIS active fire products. The developed methodology was tested in Colombia, an area not covered by any known MODIS ground antenna, using data from 2004. The resulting burned area map was validated using a high-spatial-resolution Landsat-7 Enhanced Thematic Mapper Plus (ETM1) image and compared to two global burned area products L3JRC (terrestrial ecosystem monitoring global burnt area product) and MCD45A1 (MODIS Terra 1 Aqua burned area monthly global 500-m SIN grid V005). The results showed that this method would be of great interest at regional to national scales because it proved to be quick, accurate, and cost effective. © 2011.

This paper presents an algorithm for rapid and accurate burn mapping that is applied here to the forest fires occurred in Galicia (northwest Spain) in August 2006, when nearly 930 km2 were almost entirely burned over the course of eight days. The algorithm synergistically combines remotely-sensed reflectance and active fire data as measured by the MODIS (MODerate resolution Imaging Spectrometer) sensor on board Terra and Aqua NASA (National Aeronautics and Space Administration) satellites. Burned area data collected from this work was compared to official fires statistics from the Spanish Ministry of Environment and to perimeters that were derived using a high spatial resolution satellite image. In a later step, burn patches area analyzed using information from the National Forest Map (150,000) and some Geographical Information Systems (GIS) tools. © 2009 Elsevier B.V. All rights reserved.

This paper analyses the spatial structure of the Pinus pinaster Aiton stands within Madrid province (Central Spain) by means of high spatial resolution images, as well as the relationship between texture indexes obtained from variograms, and dasometric features of forest stands. In order to carry out this research, some orthophotographs and an IKONOS satellite image were used. All these images corresponded to locations of the Spanish National Forest Inventory (NFI) sample plots for the species of interest. Image analysis was based on geostatistic tools and particularly on the variogram. Experimental variograms were calculated using the different data sets. The following step consisted on fitting mathematical functions to them in order to produce ideal variograms. These models were used to extract a set of variogram variables that might be useful for characterizing forest stands at different spatial resolutions. As a result, some significant relationships between variogram parameters and dasometric variables were found, but of limited predictive power. The latter reveals the diff iculties in applying such methodology when working on complex topographies and spatially heterogeneous forests as the Mediterranean.

The present paper presents an algorithm that synergistically combines data from four different parts of the spectrum (near-, shortwave, middle- and thermal infrared) to produce a reliable burned-area map. It is based on the use of a modified version of the BAIM (MODIS Moderate Resolution Imaging Spectrometer Burned Area Index) together with active fire information. The following study focusses in particular on an image from the AWiFS (Advanced Wide Field Sensor) sensor dated 21 August 2006 and MODIS active fires detected during the first 20 days of August as well as ancillary maps and information. The methodology was tested in Galicia (north-west Spain) where hundreds of forest fires occurred during the first 20 days of August 2006. Burned area data collected from the present work was compared with official fire statistics from both the Spanish Ministry of the Environment and the Galician Forestry Service. The speed, accuracy and cost-effectiveness of this method suggest that it would be of great interest for use at both regional and national levels. © 2009 IAWF.

The detection of forest fires and the determination of their parameters have been usually carried out by polar-orbit sensors AVHRR, (A)ATSR, BIRD, and MODIS mainly. However, their time resolution prevents them from operating in real time. In contrast, the new geostationary sensors have very appropriate capacities for the observation of the Earth and monitoring of forest fires, as is being proved. GOES, MSG, and MTSAT are already operative, and they have led the international community to think that the global observation network in real time may become a reality. The implementation of this network is the aim of the Global Observations of Forest Cover and Land Cover Dynamics (GOFC/GOLD) FIRE Mapping and Monitoring programme, focused internationally on taking decisions concerning the research of the Global Change. In this Letter, the operation in real time by the MSG-SEVIRI sensor over the Iberian Peninsula is studied. On the other hand, the reliability of validation results by means of polar sensors, with a finer spatial resolution, is difficult to analyse due to errors caused by confused location of fires. This Letter shows that fires detected by means of MSG-SEVIRI can be an useful option in order to estimate burnt areas at global scale, considering a spatial resolution of 40 km.

This study presents a rapid, accurate and economic methodology for forest fire burned areas estimation using remote sensing techniques. The algorithm used is based on thresholds identifications from infrared spectral band, using MODIS images and hotspots time series delivered from NASA. The threshold is defined by the maximum correlation between the infrared band and hotspot influence area. The results show the usefulness of the presented methodology in forest fire burned area estimation and its relevance for prioritizing forest management activities and for planning future reforestations work in the affected area.

This paper presents preliminary results of updated land use-land cover (LULC) maps for two Spanish provinces using MERIS-FR images, data from the Third National Forest Inventory (NFI3) ground plots, and the European database CORINE Land Cover 2000 (CLC2000). Legend categories were defined using the FAO legend-based European Global Land Cover (GLC2000) product. The applied methodology is based on maximum likelihood supervised classification of MERIS-FR images. The delimitation of training areas was based on the NFI3 ground plots and CLC2000. High overall accuracies were obtained for Navarra (73.67%) and Murcia (73.70%). These preliminary results show that MERIS-FR data allow an operational development of LULC maps/products at medium scales. Results from the comparison between MERIS-based classifications and available thematic maps are also presented.

This paper concerns an estimation of burned area and fire severity levels in the area affected by the Valencia de Alcántara forest fire, an event that took place near the border between Portugal and Spain in August 2003. 'Level-of-damage'and 'fire severity'are both defined as the impact of fire on the vegetation. The study presented herein uses satellite information from Envisat-MERIS (Medium Resolution Imaging Spectrometer) and SPOT5-HRG (Système pour l'observation de la Terre - High Resolution Geometric instrument), ground data and ancillary maps. The methodology consisted of applying linear unmixing algorithms on a post-fire MERIS image, using a post-fire SPOT5-HRG image and ground data for endmember definition. Satellite-derived level-of-damage information is used for affected area estimation and for comparison with fire severity ground measurements. Satellite-derived level-of-damage is also compared with information from the Spanish National Forest Map (NFM) to assess to what extent fire severity is related to particular forest types. Results reached so far reveal that MERIS estimations on wildfire damage over forested areas may help in establishing degrees of affection, which is useful to plan forest restoration works.

The present study is focused on the capabilities of remote sensing data and techniques to help in the monitoring of forest ecosystems as carbon sinks. It will attempt to find statistical relationships between satellite-derived NDVI (Normalized Difference Vegetation Index) data from SPOT-VEGETATION and NOAA-AVHRR and field measurements from the Spanish National Forest Inventory on the geographical basis of provinces. Statistically significant relationships were obtained when correlating the aforementioned datasets. These relationships were then used to predict forest biomass at a national level, in order to obtain updated forest information between consecutive National Forest Inventories.

The Mediterranean fir Abies pinsapo Boiss. in sierra del Pinar, province of Cádiz, Spain, is studied using the information of an IRS-1C WiFS satellite image and data derived from ground plots of the Second National Forest Inventory of Spain. As forest parameters have been used the number of trees, the basal area and the stem wood volume with bark. For all the ground plots in the study area there is an statistically significant relationship between stem wood volume with bark of all species and WiFS NDVI at the 90% confidence level. In the case of the plots with appreciable presence of Abies pinsapo there is an statistically significant relationship at the 95% confidence level between WiFS NDVI and both stem wood volume with bark of all species and stem wood volume with bark of Abies pinsapo. Stem wood volume with bark images were obtained for the study area, one using data from all the ground plots and other using only data from the ground plots with appreciable presence of Abies pinsapo. The relationship between the estimated percent of stem wood volume with bark of Abies pinsapo and its potentially occupied area was later analysed.

The Medium Resolution Imaging Spectrometer (MERIS) which is carried by ESA's Envisat environmental satellite, to provide wildfire damage information, is discussed. The MERIS instrument estimates the degree of damage caused by forest fires from its multi-spectral imaging capabilities in the visible and near-infrared regions of the spectrum and its narrow spectral bands. The study area known as Valencia de Alcántara, delineated on the accompanying MERIS image, for the analysis procedures. It is observed that MERIS-based estimates of wildfire damage over forested areas can be extremely useful not only in establishing the scale of the damage, but also for the subsequent forest renewal projects and for subsidy management.